Method and apparatus for determining hemoglobin based parameters in an unlysed blood sample

An apparatus for determining hemoglobin concentration within an unlysed, substantially undiluted whole blood sample, which sample includes non-red blood cell constituents, comprising:

• an analysis chamber configured to quiescently hold the sample for analysis, the chamber defined by an interior surface of a first panel, and an interior surface of a second panel, wherein both panels are transparent, and which chamber has a height extending between the interior surface of the first panel and the interior surface of the second panel, which height is no more than about twenty microns (20μ) or no less than about two microns (2μ);
• a sample illuminator configured to emit light to pass through a region of the unlysed, substantially undiluted sample quiescently residing within the chamber, which region includes red blood cells and one or more non-red blood cells constituents;
• an image dissector configured to capture light originating from the sample illuminator and passed through the sample, including the one or more non-red blood cell constituents, quiescently disposed within the chamber, and to produce image signals representative of the light passed through the sample;
• and
• an analyzer adapted to determine a sample representative optical density value using the image signals, and to determine the hemoglobin concentration of the region of the unlysed, substantially undiluted sample using the sample representative optical density value.

A method for determining a red blood cell distribution width (RDW) of a blood sample, comprising:

• depositing an unlysed, substantially undiluted blood sample into an analysis chamber adapted to quiescently hold the sample for analysis;
• imaging the sample in a region of the analysis chamber to produce image signals representative of the optical density of the imaged region, which imaged sample includes non-red blood cell constituents;
• determining a sample representative optical density value using the image signals representative of the optical density of the sample within the imaged region;
• and
• determining the RDW of the sample using the sample representative optical density value.